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Digital Video
4.1 Introduction
General
The Cougar Digital Video Routing Switcher provides switching of 32 video
inputs to 32 video outputs while supporting multiple data bit rates. The
data rates supported included: (D1, 270 Mbit/s), (D2 or D3, NTSC @ 143
Mbit/s), (D2 or D3, PAL @ 177 Mbit/s), and the proposed (compressed,
16:9 HDTV @ 360 Mbit/s).
4.2 32X32 Digital Video Matrix Card
The 32X32 Digital Video Matrix Card contains a 32X32 matrix consisting
of several main circuits. This discussion will be broken down to the main
circuits as they are found on the schematics in Section 6 (Schematics).
Control
The microprocessor controller (U56) is used to interface switch commands
from the PRCI control port (U63) to the switch matrix and return status in-
formation to the controller. Matrix input, output , and level coding is read
from the backplane through U50 thru U53. U65, U55, and U59 provide ad-
dress decoding for the 32X32 Digital Video Matrix Card.
U58 and U57 comprise the nonvolatile RAM for the processor. C242 pro-
vides memory backup voltage for approximately seven days as long as
the matrix card is not removed from the Cougar Frame. CR6 is utilized by
the processor on the 32X32 Digital Video Matrix Card to indicate a fault
condition.
Two external sync signals are used for timing switches as set by S1. The
external sync can be color black or composite sync. U69 and U71 decode
the composite signal to an even/odd field signal which is used by the mi-
croprocessor.
Crosspoint Matrix
U49 is the 32X32 crosspoint matrix switch. A0-A4 select the output buss
to control. D0-D4 select the input to be switched to the selected output.
CS0 latches the data into a hold register, then VREF1 latches the data
into the crosspoint control registers.
4/98
P/N 81905903440
Functional
Section 4
4
F UNCTIONAL
DESC RIPTI ON
page 4.1
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